Staff Software Engineer, Pentest Experience

Get to Know Us

Horizon3 is a fast-growing, remote cybersecurity company dedicated to the mission of enabling organizations to proactively find and fix and verify exploitable attack vectors before criminals exploit them. Our flagship product, the NodeZeroTM platform, delivers production-safe autonomous pentests and other key assessment operations that scale across the largest internal, external, cloud, and hybrid cloud environments. NodeZero has been adopted by organizations of all sizes, from small educational institutions to government agencies and Global 100 enterprises. It is used by ITOps/SecOps teams, consulting pentesters, and MSSPs and MSPs.

We are a fusion of former U.S. Special Operations cyber operators, startup engineers, and formerly frustrated cybersecurity practitioners. We're committed to helping solve our common security problems: ineffective security tools, false positives resulting in alert fatigue, blind spots, "checkbox” security culture, cybersecurity skills shortage, and the long lead time and expense of hiring outside consultants. Collectively, we are a team of learn it alls, committed to a culture of respect, collaboration, ownership, and results.

About the Role

We are hiring a Staff Software Engineer, Backend to anchor the technical direction of the Assessment Experience team, transforming how customers work with NodeZero to secure their environment. Assessment Experience is part of the Proactive Offense engineering organization, which builds the core NodeZero product flow: hack, prioritize, fix, verify. Proactive Offense is responsible for driving the outcome the business is built around: allow customers to find weaknesses that represent real risk, remediate them, and prove the fixes actually eliminated attack paths.

Today, NodeZero offers a fairly traditional experience to configure and run pen tests. This team is rethinking that approach to make the experience more outcome based and natural for our customers. NodeZero should feel more like a peer or coworker that customers work with to identify real risk in their environments, and less like a product they need to manage. You will design and build the backend services, APIs, and data models behind that experience.

This is a hands-on role. You will write production code, set the standard for design and operational quality, and raise the technical bar for the engineers around you. You will be expected to be a domain expert and project leader whose influence extends beyond just your team.

What You'll Be Responsible For

• Own the technical direction for Assessment Experience backend systems, from initial concept through implementation, iteration, and long-term evolution.

• Design and build scalable backend services, APIs, and asynchronous or event-driven workflows that let customers configure assessments and consume their results reliably.

• Lead architectural decisions that balance velocity, reliability, data correctness, maintainability, extensibility, and operability, and document the reasoning so others can build on it.

• Translate ambiguous product and customer goals into concrete technical strategy, architecture, and execution plans, working closely with Product, Design, and engineering leadership.

• Drive problems that cross team boundaries, partnering with teams that own attack content, integrations, and asset matching to define clean interfaces and remove systemic blockers.

• Contribute production code and set the standard for design quality, code quality, testing, observability, and safe rollout practices such as feature flags.

• Identify risks, dependencies, and tradeoffs early, and help the team sequence work across multiple concurrent initiatives, and evaluate emerging technologies, including AI-driven approaches to outcome-based, conversational experiences, recommending adoption or avoidance with clear rationale.

• Raise the technical bar through design reviews, code reviews, architecture proposals, and technical writing that other teams can adopt as standards.

• Mentor P3 and P4 engineers through thoughtful feedback, technical coaching, and frameworks that help them do the best work of their careers.

• Communicate complex technical concepts clearly to both technical and non-technical audiences, including leadership stakeholders.

• Support hiring by helping attract, interview, and calibrate strong engineering talent.

• Use customer feedback and production signals to improve how safely, clearly, and naturally customers work with NodeZero to identify real risk and act on the results.

What You'll Bring

At Staff Engineer, we look for a domain expert and project leader whose technical impact extends across the engineering organization. You may be embedded in one team, but you drive problems beyond its boundaries and set technical direction for systems that multiple teams depend on.

• Deep backend ownership. You have owned production systems and can explain the architecture, the tradeoffs, the reliability story, and what happened after launch, not only the features you helped build.

• Cross-team technical leadership. You have led ambiguous, high-impact work, aligned engineering and product partners, and influenced technical direction through credibility rather than formal authority.

• High-stakes technical judgment. You make sound decisions with incomplete information and can defend them in terms of data correctness, reliability, performance, maintainability, and safe operation.

• Leverage over output. You make other engineers better through design reviews, mentoring, documentation, and standards that outlast any single project.

• Product and customer sense. You connect backend choices to customer outcomes such as clearer priorities, faster remediation, and greater confidence that a fix worked. If you only care about code, this may not be the right role.

• Clear communication. You explain technical decisions and tradeoffs to non-technical stakeholders in writing and in person.

• Systems thinking. You think in platforms and systems, not just features, and balance security, usability, and scalability in every decision.

Required Education and Experience

• Bachelor's degree in Computer Science, Computer Engineering, or a related field, or equivalent practical experience.

• 8+ years of professional software engineering experience, including sustained ownership of production backend systems.

• Experience building backend services in at least one modern language, such as Python, Go, Rust, or TypeScript.

• Strong SQL skills and production experience with at least one relational database, including complex joins, CTEs, window functions, and deliberate schema design.

• Experience building backend services on a cloud platform (AWS, GCP, or Azure) and familiarity with Docker and containerized applications.

• Experience designing and operating APIs, services, and asynchronous or event-driven systems.

• Experience with data modeling and persistence layers for product-grade backend systems.

• Operational maturity: observability, testing, reliability practices, and a record of debugging difficult, customer-visible production problems.

• Technical design documents, architectural proposals, or engineering standards that other teams have adopted.

• A record of leading cross-team technical work and mentoring engineers.

Preferred Experience

You don't need all of these, but experience in some of the following will help you be successful quickly:

• Taking projects with diverse requirements and delivering a consistent unifying experience for customers.

• Building or consuming GraphQL backends.

• Graph databases such as Neo4j, or interest in learning them.

• Familiarity with ETL and streaming data pipelines and data processing frameworks.

• Observability stacks (for example Datadog, Prometheus, or Grafana) and service instrumentation.

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